Why did Smartbyte radically slow down my internet connection?

I performed 3 speedtest.net tests on my Dell G5: (1) an initial test (2) a test after uninstalling Smartbyte and (3) a test after uninstalling Smartbyte drivers and services. Here are the results:

With Smartbyte fully installed
PING: 16ms
Download speed: 4.86 Mbps
Upload speed: 17.98 Mbps

After removing Smartbyte
PING: 13ms
Download speed: 6.10 Mbps
Upload speed: 17.94 Mbps

After removing Smartbyte Drivers and Services
PING: 13ms
Download speed: 540.95 Mbps
Upload speed: 18.00 Mbps

As you can see my download speed went from about 4.86 Mbps to 6.10 Mbps and finally to 540 Mbps after completely removing Smartbyte. Why is Dell installing garbage like this on my computer?